1. Field of the Invention
The invention relates to a combing machine in particular for combing of cotton, having a combing roller with at least one combing segment, and conveyance means for the fiber tuft to be combed and an upper and a lower nipper for fixing the fiber tuft during engagement of the combing segment, the upper and/or lower nipper being pivotably disposed in a forward and backward direction around an axis disposed above the comb cylinder.
2. The Prior Art
A structure having such a pendulous nipper arrangement is designated as a structure according to Nasmith. Such a structure is covered, for example, in German Patent DE-PS 11 61 185.
Regardless of this particular construction, customary combing machines are normally designed in such a way that the part of the machine which conveys the fiber tuft is moved back and forth in order to make possible in an alternating manner the cyclic engagement of the combing segment and following that, the conveying or removing of the fiber tuft. Because of this back and forth movment of a comparatively large mass, the operating speed of the combing machine is considerably limited.
In connection with wool combing machines, it is already known to pivotably dispose the combing machine head, however, it is necessary to move the draw-off rollers back and forth, because the pivot bearing point of the combing machine head is located relatively far inside the area of the conveying device and therefore the draw-off rollers must be moved out of the way for reasons of space when the combing segment is intended to engage the fiber tuft.
From U.S. Pat. No. 3,922,757 an eccentric disposition of the combing segment is known in order to achieve the desired engagement geometry. However, the combing head with the nipper arrangement is moved back and forth in the customary manner.
From German Published, Non-examined Patent Application DE-OS 28 45 245 a combing machine is known having fixed draw-off rollers, but with back and forth movement of the nipper. In this reference, the problem is already pointed out that the efficiency of customary combing machines is limited because of the oscillation created by the intermittent operation, the size of which considerably depends on the mass acceleration forces of the pendulously moved nipper. To solve this problem a second drive crank for the lower nipper plate is proposed there.
From German Published, Non-examined Patent Application DE-OS 29 40 366 a flat combing machine with a nipper arrangement driven by a linkage is known, which is fastened on a suspended pendulum, the pivot bearing point of which is disposed slightly ahead of the rotating point of the combing segment between it and the draw-off rollers.